Rotor and vane assemblies, wherein a vane reciprocates transversely to an axis of rotation of a rotor as the rotor turns, find extensive use in devices such as pumps, compressors and rotary engines. The rotor and vane assembly rotates within a housing and the vane engages a sidewall of the housing which is eccentric to the axis of rotation of the rotor. This eccentric configuration allows the rotor assembly to pump liquids, compress gases, or derive power from combustion of fuel though a thermodynamic cycle.
Advantages, such as lighter weight, lower pressure forces and reduced dead space remainder volume may be obtained by making the vanes as thin as possible. However, one of the design constraints which limits the thickness of a vane is the design of the engagement between the vane and the eccentric cam arrangement which enables the vane's reciprocal motion. There is clearly an opportunity to improve the operation of rotor assemblies by improving the engagement between the vane and cam in a rotor and vane assembly.